Comparing and Ordering Decimals PPT

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Transcript Comparing and Ordering Decimals PPT

Comparing and
Rounding Decimals
Christine Berg
Edited V Hamilton
Comparing Decimals
• Decimal
Models
• Equivalent
Decimals
• Number Line
Decimal Models
Tenth
Hundredth
Equivalent Decimals
• Decimals
that represent
the same value
• Example:
0.6 is equivalent to 0.60
0.6 = 0.60
Terminal Zeroes
• Zeroes
as last
digit(s) of a number
can be removed
0.6 = 0.60
Equivalent Decimals
0.6
0.60
Comparing Decimals
Step 1:
Stack all the numbers being
compared so that all the place
values are lined up.
87.0413
87.09
Comparing Decimals
Step 2:
Add terminal zeros so there
are the same number of
decimal places
87.0413
87.0900
Comparing Decimals
Step 3:
Underline the first number
that is different in the
numbers being compared
87.0413
87.0900
Comparing Decimals
Step 4:
Looking at the underlined digit, you
can not tell which number is larger. It
does not matter if there are
additional numbers after the digit
underlined!
87.0413
87.0900 THIS NUMBER IS LARGER!
Comparing Decimals
Step 4:
Order numbers depending on
the directions given. Pay
close attention to whether
you’re supposed to order
from least to greatest or
greatest to least!
Which is greater:
0.6 or 0.58 ?
0.60
0.58
0.6 > 0.58
Which is greater:
0.6 or 0.58
0.6
0.58
Rounding Decimals
Step 1:
Underline decimal
place we are
rounding
Rounding Decimals
Step 2:
Circle the number to
the right of the
underlined decimal
place
Rounding Decimals
Step 3:
If circled digit is greater
than or equal to 5, then
round the underlined
number up (add one)
Rounding Decimals
Step 4:
If circled digit is less
than or equal to 4,
leave the underlined
number the same
Rounding Decimals
Try these:
1)Round 1.05 to the
nearest tenth
2) Round 0.123 to the
nearest tenth
Rounding Decimals
Answers:
1) 1.1
2) 0.12
In your Own Words
Describe what you
learned today about
either reading OR
rounding decimals.